Iran's shopping list reveals their intentions.

Missile accuracy appears to be a key Iranian goal. In one of Mr. Morgenthau's cases -- the prosecution of Chinese citizen Li Fang Wei and his LIMMT company for allegedly scamming Manhattan banks to slip past sanctions on Iran -- the DA uncovered a list that included 400 sophisticated gyroscopes and 600 accelerometers. These are critical for developing accurate long-range missiles. He also found that Iran was acquiring a rare metal called tantalum, "used in those roadside bombs that are being used against our troops in Iraq and Afghanistan." So much for the media notion that Iran has played no part in killing American GIs.

The briefest of visits to Wikipedia shows tantalum has another use far more sinister than roadside bombs:

Tantalum has been proposed as a "salting" material for nuclear weapons (cobalt is another, better-known salting material). A jacket of ¹⁸¹Ta, irradiated by the intense high-energy neutron flux from an exploding thermonuclear weapon, would transmute into the radioactive isotope ¹⁸²Ta with a half-life of 114.43 days and produce approximately 1.12 MeV of gamma radiation, significantly increasing the radioactivity of the weapon's fallout for several months. Such a weapon is not known to have ever been built, tested, or used.

The typical fallout from a fission bomb will tend to subside to relatively safe levels in about two weeks (this depends upon a number of factors, of course). Salting the same bomb with tantalum could extend this fallout period to one or two years (again, depending upon a number of factors). That sucks.

I wonder if Iran developed their nuclear know-how from Wikipedia.